Critical phase control of the charge-orbital ordered manganite thin films

Utilizing the tetragonal symmetry breaking on (110) substrates, we realized a first-order phase transition arising from the charge-orbital ordering (COO) in epitaxial thin films for two types of representative COO materials, (Pr,Ca)MnO3 and (Nd,Sr)MnO3. In addition, we demonstrated a dramatic substrate-dependent crossover from charge-ordered insulator to metal for (Nd,Pr)0.5Sr0.5MnO3 as proof of the control of the one-electron bandwidth by an anisotropic substrate-induced strain. The critical phase control of spin, charge, and orbital ordering in the perovskite manganite epitaxial thin films demonstrated here constitutes a breakthrough toward strongly correlated electron devices in oxide electronics.